Typically, a personal video recorder (“PVR”) refers to a device that records video in a digital form to a disk drive or other memory medium within a device. The PVR may include a set-top box, portable media player (“PMP”) and computer software, which enables video capture and playback to and from disk. In a typical PVR configuration (e.g., TiVo), the player and storage functions are contained within the same device. This eliminates the ability to reach remote discrete players.
In a network PVR configuration provided, for example, by Cablevision, the player and storage functions are implemented on discrete networked devices, using private protocols for trick mode operations.
FIG. 1 shows a typical network PVR configuration. A network PVR configuration 100 has a network 101 (e.g., server, gateway) and clients 103 and 104. Network 101 may have a storage 102 for storing a multimedia content. Clients 103 and 104 may have a set top box and a player (not shown) to receive and play the multimedia content.
Generally, trick modes are user operations that allow random access to the multimedia content. Scan trick mode operations, e.g., simulating the fast forward and reverse scanning action of the video tape (“Scanning”), may be implemented through interpretation of the navigation information (“indexing information”) associated with the streaming media content by the multimedia player at the client. The navigation information may be in various multimedia standards and specifications that define the syntax and carriage of indexing information, e.g., the DVD Forum, the Blu-ray Disc Association, DivX specifications for DivX content, Microsoft Streaming Format for ASF container, and others.
In the existing network PVR configurations, a scan trick mode operation is performed by both network server 101 and client 103. For example, to perform 16× scan at client 103, the multimedia content may be decimated at network server 101 and stitched at client 103. Generally, decimation may refer to a technique of reducing the number of samples of a time dependent signal that represents the streaming multimedia content.
Stitching may refer to a technique of combining the samples of time dependent signal that represents the streaming multimedia content. Typically, when a trick mode operation is performed, the client implements a video sample selection and combination method so that no visual artifacts are presented from an incoming decimated stream.
The typical scan trick mode operation relies both on the capability of the content to be streamed faster than its nominal 1× playback rate from the network server and on interpretation of metadata by a player rendering the multimedia content at the client. That is, in the existing network PVR configurations a trick mode operation depends on a player at a client.
The player at the client is required by the network server to perform certain actions (e.g., stitching) for the trick mode to occur. If the player at the client (e.g., client 104) cannot recognize the actions that are required by the network server to perform, the trick mode operation cannot be accomplished. As a result, existing network PVR configurations eliminate the ability to work with retail players.
Further, in some existing network PVR configurations, multiple encoded versions of each asset are created in advance for each potential scan speed and streamed on demand. However this solution may not apply to broadcast content as it will take large amount of bandwidth and disk space to distribute and store multiple encoded versions of each asset for each potential scan speed.